I was using Fuelly.com before Acar became part of the mix. When I started using Acar I stopped entering fillups on Fuelly.com because Acar was more convenient (on my phone) and offered more than just gas mileage.

The new Sync feature did something strange. I own 2 cars, the first time it synced it added 2 more, so now I have duplicate records for them. Apparently I have 2 Infinitis and 2 Nissan 300zx's. On my phone in Acar and online at Fuelly.com

How do I merge the files? Or should I try deleting one? If I delete the records from fuelly.com (because those sets don't have any maintenance info) is there a safe way to do it?